Central Mexico Maize Yield Reconstruction: 1474-2001 ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Central Mexico Maize Yield Reconstruction: 1474-2001 LAST UPDATE: 9/2006 (Original receipt by WDC Paleo) CONTRIBUTOR: Matthew D. Therrell, University of Arkansas IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2006-084 SUGGESTED DATA CITATION: Therrell, M.D., et al. 2006. Central Mexico Maize Yield Reconstruction: 1474-2001. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2006-084. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Therrell, M.D., D.W. Stahle, J. Villanueva Diaz, E.H. Cornejo Oviedo, and M.K. Cleaveland. 2006. Tree-ring Reconstructed Maize Yield in Central Mexico: 1474–2001. Climatic Change, Vol. 74, No. 4, pp.493-504, February 2006. doi: 10.1007/s10584-006-6865-z. ABSTRACT: Maize was domesticated more than 6,000 years ago in central Mexico, and remains a vital staple food and cultural symbol in Mesoamerica. Maize yield in the central highlands is strongly dependant on adequate rainfall early in the growing season (April–June) because late maturation of the crop may result in damage from autumn frost. Climate-induced crop failures with profound socioeconomic impacts have punctuated Mexican history. However, reliable records of maize harvest have not been available until very recently, and historical records of crop yield and price are discontinuous and can be difficult to interpret. We have developed a continuous, exactly dated, tree-ring reconstruction of maize yield variability in central Mexico from 1474 to 2001 that provides new insight into the history of climate and food availability in the heartland of the Mesoamerican cultural province. The reconstruction indicates that seven of the most severe agricultural crises in Mexican history occurred during decadal-scale episodes of reconstructed maize shortfalls. GEOGRAPHIC REGION: Central Mexico PERIOD OF RECORD: 1474-2001 AD FUNDING SOURCES: National Science Foundation (USA) Paleoclimate (ATM-9986074 and 0400713) and Geography and Regional Science Programs, the National Geographic Committee for Research and Exploration, and the Inter-American Institute for Global Change, Tree Lines Project. DESCRIPTION: 205 radii from 85 trees and fallen logs from the relict stand of ancient Douglas-fir at Cuauhtemoc la Fragua, Puebla, were used to compile earlywood, latewood, and total ring width chronologies extending from 1474–2001. The latewood chronology has been used to develop a high quality reconstruction of annual maize yield for the late prehispanic, colonial, and modern eras in the heart of highland Mexico. For this study we use maize "yield" data from the three states of Puebla, Tlaxcala, and Veracruz compiled by the Secretaria de Agricultura, Ganaderia, Desarrollo Rural, Pesca y Alimentacion. The yield data represent statewide average production in tonnes (1000 kg) per ha. The average three-state yield over the 22-year period is 1.65 t/ha. The overall correlation (r) between the latewood (LW) chronology and the combined three state maize yield from 1980 to 2001 is 0.79. The regression equation Yt = 0.796 + 0.862Xt explains 60% of the maize yield variability (Yt is the estimated maize yield (tonnes per hectare) for year t, and Xt is the corresponding Cuauhtemoc LW value in year t. Following calibration and verification, the observed and reconstructed maize yield data were normalized and represent standardized anomalies from the calibration period mean (1.65 t/ha). DATA: Observed and reconstructed maize yields. Normalized values based of yield in tonnes per hectare. Column 1: Calendar Year AD Column 2: Tree-ring Reconstructed Maize Yield (1474-2001) Column 3: Observed Maize Yield (1980-2001) Year Recon. Observed 1474 -1.733 1475 -1.261 1476 -1.016 1477 -0.106 1478 -1.58 1479 -0.937 1480 -0.277 1481 1.171 1482 0.419 1483 0.563 1484 1.202 1485 0.699 1486 0.458 1487 0.638 1488 0.769 1489 0.113 1490 2.033 1491 0.769 1492 -0.194 1493 1.25 1494 1.407 1495 -0.089 1496 0.865 1497 3.652 1498 0.651 1499 0.537 1500 -0.679 1501 0.659 1502 0.454 1503 1.018 1504 0.187 1505 0.336 1506 1.359 1507 0.209 1508 -0.233 1509 1.613 1510 1.499 1511 1.823 1512 1.779 1513 0.651 1514 1.827 1515 1.132 1516 0.83 1517 -0.146 1518 0.449 1519 1.98 1520 0.209 1521 0.699 1522 -0.001 1523 0.445 1524 -0.132 1525 -0.163 1526 -0.006 1527 -0.447 1528 -0.583 1529 0.244 1530 -0.312 1531 -0.119 1532 -0.172 1533 0.423 1534 -0.154 1535 0.126 1536 0.305 1537 0.882 1538 -0.456 1539 0.196 1540 -0.39 1541 -0.286 1542 -0.548 1543 -0.552 1544 -0.657 1545 -0.81 1546 -1.139 1547 -1.191 1548 -1.388 1549 -1.747 1550 -2.027 1551 -1.069 1552 -1.095 1553 -1.554 1554 -1.125 1555 -0.565 1556 -0.596 1557 -0.207 1558 -0.443 1559 -1.537 1560 -0.351 1561 -0.517 1562 -1.821 1563 -1.388 1564 -1.314 1565 -0.132 1566 0.218 1567 -0.312 1568 0.944 1569 -0.509 1570 2.418 1571 0.371 1572 -0.041 1573 0.06 1574 0.966 1575 -0.049 1576 0.935 1577 0.638 1578 1.849 1579 1.071 1580 1.071 1581 0.436 1582 0.467 1583 1.123 1584 -0.408 1585 -0.474 1586 -0.631 1587 -0.124 1588 1.569 1589 1.254 1590 1.176 1591 3.078 1592 1.372 1593 0.817 1594 0.095 1595 -0.955 1596 -1.073 1597 -2.328 1598 -1.646 1599 -1.782 1600 -1.79 1601 -0.898 1602 -0.701 1603 -0.64 1604 -1.086 1605 -1.637 1606 -1.309 1607 -1.073 1608 -0.701 1609 0.274 1610 -0.526 1611 -1.178 1612 0.576 1613 1.609 1614 -0.347 1615 0.323 1616 -0.294 1617 0.13 1618 1.057 1619 0.043 1620 -0.36 1621 -0.22 1622 -1.379 1623 -1.475 1624 -0.355 1625 -1.156 1626 -0.649 1627 -0.723 1628 -0.181 1629 -0.001 1630 -0.351 1631 -0.841 1632 -0.793 1633 0.008 1634 0.069 1635 0.743 1636 0.642 1637 0.126 1638 0.064 1639 -1.563 1640 -0.29 1641 -1.187 1642 -0.775 1643 -0.364 1644 0.843 1645 0.533 1646 1.744 1647 1.674 1648 -0.264 1649 -0.027 1650 0.165 1651 1.294 1652 0.078 1653 -0.001 1654 -0.377 1655 -0.495 1656 1.053 1657 0.48 1658 1.272 1659 0.419 1660 0.454 1661 3.188 1662 0.091 1663 0.887 1664 0.401 1665 1.355 1666 -0.277 1667 -0.395 1668 -0.22 1669 -0.815 1670 -0.071 1671 0.305 1672 2.23 1673 -0.137 1674 -1.239 1675 -0.369 1676 0.773 1677 0.2 1678 -0.303 1679 -0.307 1680 -0.465 1681 -0.08 1682 -0.176 1683 1.941 1684 0.843 1685 1.495 1686 1.827 1687 0.55 1688 0.091 1689 0.06 1690 -0.189 1691 0.043 1692 0.961 1693 -0.369 1694 -0.049 1695 -0.421 1696 -1.795 1697 -1.143 1698 -1.034 1699 -0.867 1700 -0.631 1701 -1.2 1702 -1.572 1703 -1.852 1704 -1.856 1705 -1.545 1706 -0.929 1707 -1.335 1708 -0.88 1709 0.288 1710 -0.736 1711 -0.946 1712 -0.185 1713 0.069 1714 0.966 1715 -0.32 1716 0.012 1717 -0.53 1718 0.134 1719 0.187 1720 -0.929 1721 -0.189 1722 -0.141 1723 0.288 1724 0.694 1725 -1.178 1726 -0.802 1727 -0.662 1728 1.101 1729 1.123 1730 -1.305 1731 -0.942 1732 0.279 1733 -0.412 1734 0.624 1735 -0.159 1736 0.935 1737 1.482 1738 0.729 1739 0.34 1740 0.266 1741 0.546 1742 0.489 1743 0.169 1744 1.989 1745 0.152 1746 0.655 1747 0.966 1748 1.005 1749 1.399 1750 2.177 1751 0.922 1752 1.779 1753 0.541 1754 -0.163 1755 -0.386 1756 -0.154 1757 -0.487 1758 -0.854 1759 -0.504 1760 -0.74 1761 -1.029 1762 -1.099 1763 0.288 1764 0.296 1765 -0.176 1766 -0.141 1767 -0.097 1768 -0.141 1769 0.318 1770 -0.399 1771 1.731 1772 -0.189 1773 -0.968 1774 -0.705 1775 -0.163 1776 0.498 1777 0.279 1778 -0.22 1779 -0.084 1780 2.414 1781 0.029 1782 0.445 1783 0.913 1784 0.143 1785 0.607 1786 0.187 1787 -1.65 1788 -0.924 1789 -1.567 1790 -2.298 1791 -0.719 1792 0.362 1793 -0.111 1794 0.9 1795 0.253 1796 0.152 1797 -0.487 1798 -0.334 1799 -0.863 1800 0.196 1801 -0.137 1802 -0.137 1803 0.498 1804 4.111 1805 1.919 1806 0.174 1807 0.406 1808 0.856 1809 -1.178 1810 -0.487 1811 0.139 1812 -0.023 1813 0.773 1814 1.316 1815 -1.134 1816 -1.182 1817 -0.452 1818 -0.307 1819 -0.268 1820 0.358 1821 -0.181 1822 -1.217 1823 -0.377 1824 0.681 1825 0.668 1826 0.008 1827 0.375 1828 1.285 1829 0.366 1830 0.025 1831 1.171 1832 0.309 1833 1.381 1834 0.187 1835 -1.72 1836 -1.314 1837 -0.574 1838 -1.331 1839 -2.193 1840 -1.405 1841 -0.705 1842 -1.532 1843 -1.493 1844 1.246 1845 0.686 1846 -0.412 1847 0.563 1848 0.353 1849 0.349 1850 1.267 1851 0.515 1852 1.377 1853 0.2 1854 2.16 1855 0.799 1856 1.644 1857 0.559 1858 -0.172 1859 1.127 1860 1.731 1861 -0.058 1862 0.764 1863 -0.701 1864 -0.054 1865 -0.019 1866 -0.106 1867 -0.797 1868 -1.09 1869 -0.132 1870 -0.22 1871 -0.657 1872 -1.104 1873 -0.942 1874 -0.482 1875 -0.561 1876 0.546 1877 1.184 1878 -2.04 1879 -0.937 1880 0.156 1881 -0.163 1882 0.003 1883 0.331 1884 0.008 1885 -1.038 1886 0.099 1887 -1.191 1888 1.092 1889 1.324 1890 -0.863 1891 -0.815 1892 0.651 1893 -0.679 1894 -1.348 1895 -2.355 1896 -2.315 1897 -1.882 1898 0.283 1899 0.939 1900 -1.637 1901 -0.535 1902 -0.894 1903 -1.104 1904 0.148 1905 1.954 1906 1.915 1907 2.029 1908 0.909 1909 -0.631 1910 -0.859 1911 0.55 1912 0.235 1913 1.036 1914 -0.39 1915 0.519 1916 -0.041 1917 0.336 1918 -0.535 1919 -0.351 1920 1.351 1921 0.826 1922 -0.268 1923 1.902 1924 -0.189 1925 0.773 1926 1.998 1927 0.371 1928 0.139 1929 -1.265 1930 0.047 1931 -0.325 1932 -0.439 1933 -1.799 1934 -0.57 1935 -0.723 1936 -0.119 1937 0.445 1938 0.244 1939 -0.6 1940 -0.312 1941 -0.452 1942 1.412 1943 -0.369 1944 -0.539 1945 0.274 1946 -0.382 1947 0.393 1948 -0.596 1949 -1.471 1950 0.83 1951 0.594 1952 1.018 1953 1.333 1954 -0.084 1955 1.438 1956 1.727 1957 -0.434 1958 -0.885 1959 0.209 1960 -0.43 1961 -0.723 1962 -1.895 1963 -1.9 1964 -1.935 1965 -1.685 1966 -0.128 1967 -1.191 1968 0.331 1969 1.206 1970 -1.069 1971 -1.335 1972 -0.202 1973 -0.968 1974 0.983 1975 0.314 1976 0.865 1977 -0.408 1978 -0.469 1979 -0.964 1980 -0.281 -0.057 1981 0.082 0.286 1982 -0.32 -1.321 1983 -1.637 -1.985 1984 -1.003 -0.031 1985 -0.001 0.153 1986 -0.771 -1.199 1987 -0.447 -0.857 1988 -1.274 -1.236 1989 0.008 -0.289 1990 -0.049 0.485 1991 0.428 0.485 1992 1.967 1.775 1993 0.458 0.669 1994 0.309 -0.326 1995 1.635 0.632 1996 2.978 1.318 1997 0.541 -0.525 1998 -1.353 -0.842 1999 0.025 0.006 2000 0.681 1.281 2001 0.502 1.576